The present invention pertains to the connection between the lower end of a side wall plate and the bottom plate of a large container.
It has been known in the manufacture of large containers from prefabricated sandwich panels that the sandwich panel for the container bottom is not filled with foam up to the edges that belong together during its preparation, but the solid foam block formed between the cover plates is allowed to end offset in the inward direction in relation to the plate edges. A bottom plate thus prefabricated and a likewise prefabricated side wall plate are laid or inserted in a mold, and a free space, which is temporarily covered by wall parts of the mold, is formed in the area between the front sides of the support foam layers of the bottom plate and the side wall plate. The components of the support foam are introduced into the chamber thus formed, which is closed on all sides, and filled with foam. During solidification, the support foam becomes firmly connected to the front sides of the support foam layers of the side wall and the bottom, but not to the wall parts of the mold due to their special pretreatment. Once the support foam has solidified and become firmly connected to the support foam layers of the side wall and the bottom as well as parts of the cover plates of the side wall and the bottom, the mold walls are removed, and the solid foam body, lying exposed in the transition area, is planked, so that a double wall, which is led beyond the edge between the bottom plate and the side wall and consists of two cover plates and a continuous solid foam layer, is obtained.
It has also been known that the planking of the support foam in the transition area can be placed into the mold prior to the formation of the support foam, so that the support foam also forms a firm connection with it during solidification, and the finished connection is obtained when the container is removed from the mold, or the mold is removed from the container.
In particular, a corner connection has been known, in which the corner area initially left free between the bottom plate and a wall plate of the container, both of which were made as sandwich panels and then assembled, is filled with foam on the site (in situ), while the transition walls between the bottom plate and the wall plate are initially still missing and are replaced by plates of a die, the hollow space thus formed is filled with foam, and an outer cover profile is glued to the foam body after the latter has solidified and comes into contact from the outside with the outer cover plate of the side wall and a surface of the bottom plate, while an inner cover profile is hung in a hinge of the upper bottom cover plate and is folded onto the outside of the inner side wall cover plate (DE 40 03 929). In the folded-up position, the inner cover profile is then glued or connected in another suitable manner to the support foam of the transition area and possibly the inner side wall cover plate. In the folded-up position, the inner cover profile forms, at its upper end, together with the inner side wall cover plate, a groove or channel, into which a sealing cord is pressed in order to prevent liquid from penetrating into the side wall and possibly even into the bottom, because the support foam layer would otherwise roll off. This necessary design of a seal is not only expensive, but also represents a source of hazard, because tools may be caught in the channel during work, and the channel wall formed by the inner cover profile may be extended and may break off.